Search Publications
Atmosphere Models of Brown Dwarfs Irradiated by White Dwarfs: Analogs for Hot and Ultrahot Jupiters
Lothringer, Joshua D.; Casewell, Sarah L.
Irradiated brown dwarfs (BDs) provide natural laboratories to test our understanding of substellar and irradiated atmospheres. A handful of short-period BDs around white dwarfs (WDs) have been observed, but the uniquely intense UV-dominated irradiation presents a modeling challenge. Here, we present the first fully self-consistent 1D atmosphere mo…
A Model for Coronal Inflows and In/Out Pairs
Lynch, Benjamin J.
This report presents a three-dimensional (3D) numerical magnetohydrodynamics (MHD) model of the white-light coronagraph observational phenomena known as coronal inflows and in/out pairs. Coronal inflows in the Large Angle and Spectrometric Coronagraph/C2 field of view (approximately $2\mbox{--}6\,{R}_{\odot }$ ) were thought to arise from the dyna…
Structural and Dynamical Analysis of 0.1 pc Cores and Filaments in the 30 Doradus-10 Giant Molecular Cloud
Lebouteiller, Vianney; Indebetouw, Rémy; Wong, Tony +4 more
High-resolution (<0.1 pc) Atacama Large Millimeter/submillimeter Array (ALMA) observations of the 30Dor-10 molecular cloud 15 pc north of R136 are presented. The 12CO 2-1 emission morphology contains clumps near the locations of known mid-IR massive protostars, as well as a series of parsec-long filaments oriented almost directly tow…
Resolving Decades of Periodic Spirals from the Wolf-Rayet Dust Factory WR 112
Moffat, Anthony F. J.; Stevens, Ian R.; Sakon, Itsuki +9 more
WR 112 is a dust-forming carbon-rich Wolf-Rayet (WC) binary with a dusty circumstellar nebula that exhibits a complex asymmetric morphology, which traces the orbital motion and dust formation in the colliding winds of the central binary. Unraveling the complicated circumstellar dust emission around WR 112 therefore provides an opportunity to under…
Surface Brightness Evolution of Galaxies in the CANDELS GOODS Fields up to z ∼ 6: High-z Galaxies Are Unique or Remain Undetected
Conselice, C. J.; Duncan, K.; Spitler, L. R. +1 more
We investigate the rest-frame ultraviolet (UV, λ ∼ 2000 Å) surface brightness (SB) evolution of galaxies up to z ∼ 6 using a variety of deep Hubble Space Telescope (HST) imaging. UV SB is a measure of the density of emission from mostly young stars and correlates with an unknown combination of star formation rate, initial mass function, cold gas m…
The High-mass Protostellar Population of a Massive Infrared Dark Cloud
Zhang, Yichen; Tan, Jonathan C.; Lim, Wanggi +3 more
We conduct a census of the high-mass protostellar population of the ∼70,000 M⊙ infrared dark cloud (IRDC) G028.37+00.07, identifying 35 sources based on their 70 µm emission, as reported in the Herschel Hi-GAL catalog of Molinari et al. We perform aperture photometry to construct spectral energy distributions, which are then fit w…
Gemini Near-Infrared Field Spectrograph Observations of the Seyfert 2 Galaxy Mrk 3: Feeding and Feedback on Galactic and Nuclear Scales
Kraemer, S. B.; Crenshaw, D. M.; Storchi-Bergmann, T. +10 more
We explore the kinematics of the stars, ionized gas, and warm molecular gas in the Seyfert 2 galaxy Mrk 3 (UGC 3426) on nuclear and galactic scales with Gemini Near-Infrared Field Spectrograph observations, previous Hubble Space Telescope data, and new long-slit spectra from the Apache Point Observatory (APO) 3.5 m telescope. The APO spectra are c…
Discovery of 18 Stars with -3.10 < [Fe/H] < -1.45 in the Sagittarius Dwarf Galaxy
Frebel, Anna; Chiti, Anirudh; Hansen, Kylie Y.
Studies of the early chemical evolution of some larger dwarf galaxies (>107 M⊙) are limited by the small number of stars known at low metallicities in these systems. Here we present metallicities and carbon abundances for eighteen stars with metallicities between -3.08 ≤ [Fe/H] ≤ -1.47 in the Sagittarius dwarf spheroidal g…
The Streamer Blowout Origin of a Flux Rope and Energetic Particle Event Observed by Parker Solar Probe at 0.5 au
Luhmann, J. G.; Lario, D.; Arge, C. N. +18 more
The distribution of spacecraft in the inner heliosphere during 2019 March enabled comprehensive observations of an interplanetary coronal mass ejection (ICME) that encountered Parker Solar Probe (PSP) at 0.547 au from the Sun. This ICME originated as a slow (∼311 km s-1) streamer blowout (SBO) on the Sun as measured by the white-light c…
Detection of the Red Supergiant Wind from the Progenitor of Cassiopeia A
Chevalier, Roger A.; Raymond, John C.; Milisavljevic, Dan +4 more
Cassiopeia A (Cas A) is one of the best studied young Galactic supernova remnants. While it provides a rare opportunity to study in detail the remnant of a supernova (SN) type IIb, questions remain regarding the nature of its progenitor, its mass-loss history, and its pre-SN evolution. Here we present an optical investigation of the circumstellar …